The blood pressure of a patient can be monitored by direct coupling of the patient's circulatory system to a pressure transducer assembly. In this event, the patient's blood, or a fluid in direct contact with the patient's blood, is provided to the transducer assembly. The transducer assembly converts the pressure of the blood to an electrical signal related to the blood pressure, and this signal can be appropriately displayed or recorded by a monitor.
A transducer assembly includes two primary components, i.e., a dome and a transducer. The dome is coupled to tubing, such as IV tubing, which may lead to the patient and elsewhere. The interior of the dome is in communication with the circulatory system of the patient and is a disposable component which is typically thrown away periodically along with any associated IV system. The transducer is a permanent part of the system which senses the pressure of the fluid received by the dome and converts it to a related electrical signal.
Because the dome is disposable, domes must be attached to, and detached from, the transducer many times. Accordingly, it is important that the coupling between the dome and transducer be easily locked and released without disturbing the tubing or the sensing portion of the transducer. One technique for attaching the dome to the transducer, which is illustrated in Minior et al U.S. Pat. No. 4,185,641 involves relative rotation between the dome and the transducer. Rotation of the dome twists the tubing coupled to it so that the attending technicians may have difficulty in determining where each tube runs. Turning the transducer, on the other hand, twists the electrical cords coupled to the transducer and can cause early failure of the cords.
Another prior art connection between the dome and transducer, which is illustrated by way of example in Lee U.S. Pat. No. 4,072,056 employs a bezel which must be rotated relative to both the dome and the transducer. It is difficult for the attending technician to hold the dome and transducer stationary while turning the bezel.